Identity and Similarity

Aligned sequences

Sequence type

Output

How to calculate identity and similarity

Paste an alignment in FASTA format, with gaps written as -.
Choose whether it is DNA or protein.
Every pair of sequences is listed with the number of positions compared, the identity and, for proteins, the similarity.

Frequently asked questions

Which positions are compared?

Positions where neither sequence has a gap. Identity and similarity are percentages of those positions.

What counts as similar?

Residues in the same group: GAVLI, FYW, CM, ST, KRH, DENQ and P.

Is my sequence uploaded?

No. Everything runs in your browser, so your sequences never leave your device.

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Guides

How to Align Two DNA or Protein Sequences How to Calculate Percent Identity and Similarity